Torsion rod spring suspension



Nov. 14, 1944.

A. F. HlcKMAN K TORSION ROD SPRING SUSPENSION 2 Sheets-sheet 1 Filed Febg, 25, 1942 NOV. 14, 11944, A, F, HlKMAN 2,332,483

TORSIQN ROD SPRING SUSPENSION I Filed Feb, 25, 1942 i .'2A SheetSfShSe 2 WNNHNWMHU .INVE i'OR @6MB 0MM ATTORNEYS I .EVA//// bv mwmmfw. bv m i l l I l l I l l l i l 'Il wwwkNm/ a w mh www@ s* Sw @n www Sw Mv gw@ um www @www lhtentecliNov. 14, 1944 'roRsIoNRon SPRING SUSPENSION f Albert F. HickmamEden, N. Y., assigner to Hick-` man Pneumatic Seat Co., Inc., Eden, N. Y., a corporation ot'New York y l Application February 26, 1942,.Serial No.- 432,405

1o claims. (ci. 2er-57) t i' "I'hisinvention vrelates'to a torsion rod spring suspensionfor vehicles and more particularly to sucha spring. suspension in which the axle is permitted to -move` against a 'geometric `resilient resistance, both laterally and vertically, relative tothe vehicle frame, both when thevehicle has alow .percentage ofload variation and also when it has a high percentage of load` variation.

. terially reduce the weightof the tandem axle sus- -While the invention is more particularlyv dei,

scribed 4in connection with a highway vehicle, it

is `also, applicable for use on other land vehicles, i

such f asrailroad cars.

This applicationv is a continuation in part of my-copending application Ser. No. 319,097, led February l5, 1940, now Patent No. 2,290,181, --granted July 21, 1942, for Tandem axle'suspension andisacompanion applicationto my. applicationzSer. No. 432,404, flied of even date here'- with, .now 'Patent No., 2,333,650, granted Novem berc9, '1943. 1

One of theobjectsof the invention is toireduce and cushion` the lateral impacts irom'the :axle against 'eitherthe frame .or the springs of` a vehicle rwhich-isfsubject to either'a'high or a lowpercentage'of loadv variation. i

Another object is-to-provide such a spring suspension in'which the'movements of the axle `both vertically .and laterally, are opposed by, a

spring-suspensions now in use.

pension as compared with conventional leaf This is accomplished'ibyfsubstituting short levers and light torsion rods for the conventional leaf springs and by the elimination of cross shaft stabilizers.

- -Another objectrof the invention is ytoprovide aspring suspensiongin which the torsionrods, in addition to serving as the spring means between the axle and the frame, 'also serve as journal pins for pivotally connecting the axles to the frame.

- Another object of the `invention is to include `geometricresilient resistance and in which the movements of the axle are opposed by a yresilient i'orve of such vnature as to take care of ahighv `percentage of load variation so that,

regardless `of whether the vehicle is loaded or unloaded, no undue :end thrusts are imposed on the various pivotal connections which connect the-axle to the frame.

Another objectis toprovide such a torsion rod spring suspension in which geometric resilient resistance is obtainedV in a compact structur which-'requires no lubrication.

Another object of the invention is to provide suchfa. suspension in which the distribution of theload. vfrom the axle to the frame is ata plurality of points 'and in which all drive and Abraketorque lis resisted by the linkage ofthe suspension itself so as to avoid the necessity of radius rods or like mechanism.`

Another obiect of the invention is toy avoid all leaf 'springfriction by the use of torsion vrodsA and avlinkageconnection between the frame and "the'axle With heavy vehicles supported on leaf springs, theleaf spring friction is extremely high `whenthe vehicle is unloaded so as to render the vehicle practically unsprung.

Another object of the invention is to vary mabushings of rubber or other soft, resilient plastic kmaterial in the bearings for the torsion rods and drawings:

1 is a fragmentary top plan view of the frame of a vehicle supported on an axle by a torsion rod spring suspension embodying my invention. y g

Fig. `2 is a lfragmentary vertical longitudinal section, taken on line 2 2, Fig..l.

'Fig. 3, is an enlarged fragmentarytransverse section thereof, taken generally on line 3 3, Fig. 2. Y f

Fig. 4 is a laid-,out section through the-linkage pivotally connecting each end of veach axle withtheframe, this section being taken generally online 4--4,"Fig.3.

Figs. 5,V 6 and 7 are enlarged fragmentary'trans'- verse sectional'views, taken on vthe correspondingly numbered lines Vof Fig. 4. o

Fig. 8 is a view similar to Fig. 4showinga modiled form of the invention.

l"Ihe invention is shown in connection with' a highway vehicle, although the invention yis also applicable to railroad cars or other land vehicles. 'lhe frame lll of the vehicle is shown as including a pairof longitudinal side frame `bars I lv suitably joined together transversely by cross frame'bars lI2' in the usual and well known manner. This frame isshownas supported byan axle l 3 which is supported by a pair of Wheels I4, th'ese Wheels being rotatably secured-to the axles.

To each end of each axle is secured anaxle bracket I5 which is fast tothe axle and extends upwardly therefrom and is formed to provide an inwardly projecting arm or horn I6 at its upper end. At its upper inner extremity, this axle bracket I5 pivotally carries an axle pivot pin I1 which, as best shown in Fig. 4, is preferably mounted in a bushing I8 of rubber or other soft, resilient plastic material having a tubular metal lining sleeve I9 which is tightly tted around the axle pivot pin I1 and has a tubular metal outer sleeve 2U which is fitted in a bore 2I in the upper inner extremity of the axle bracket I5, this outer sleeve 2D being held against rotation in the bore 2I by set screws 22 or in any other suitable manner. The rubber connection between each axle bracket I5 and its axle pivot pin I1 permits the axle pivot pin I1 to oscillate in the axle bracket I5 the necessary extent to permit vertical and lateral movement of each axle relative to the frame I as hereinafter described and avoids the necessity of providing a bearing which requires lubrication or which may become noisy. As best shown in Fig. 4 the inner metal lining sleeve I9 of the rubber bushing for the axle pivot pins I1 is extended outwardly beyond the front and rear extremities of the axle bracket I and forms a spacer for ra pair of shackles and 26. The shackle 25 is welded to the corresponding end of the axle pivot pin I1 and one end of the shackle 26 is secured to the opposite threaded end of the axle pivot pin I1 by means of a nut 21.

The other ends of the shackles 25 and 26 are similarly secured to the opposite ends of a crank arm. pivot pin`30, this crank arm pivot pin 30 being tightly fitted in the inner metal lining sleeve 3| of a bushing 32 of rubber or other soft, resilient plastic material with this inner metal lining sleeve 3| forming a spacer for the two shackles 25 and 26. The rubber bushing 32 is surrounded by an outer metal sleeve 33 which is secured in the bore 34 at the outer end of a crank arm 35 by means of set screws 36. lThis crank arm 35 is rotatably mounted on a torsion rod 31 which is in turn journaled in vbearings secured to the main frame I0 of the vehicle, the torsion rod 31 thereby serving both as the springing means for the suspension and also as the journal pin for the crank arm 35.

For this purpose each crank arm 35 is extended a substantial extent lengthwise of the vehicle and each crank arm is provided at its front and at its rear end with a pair of spaced bearings which embrace the corresponding parts of the companion torsion rod 31. Each of these bearings 49 is shown, asbest illustrated in Figs. 4 and 6, as comprising a half bearing 4I t formed in the crank arm 35 and a half bearing cap 42 secured to the half bearing 4I by screws 43 and embracing a bushing 44 of rubber or other soft, resilient plastic material which is tightly compressed against the torsion rod 31.

In the form of the invention shown in Figs. 1-7, the same tube of rubber serves as the rubber bushing 44 for each of the crank arm bearings 40, this rubber sleeve being secured to the torsion rod 31 by a ring clamp 45 and extending through each of the bearings 4I), as best shown in Fig. 4. By this means dirt or other abrasive material is prevented from entering the rubber bushed bearings 40 and hence the life of these rubber hushed bearings is materially increased. The use of the rubber sleeve 44 as the bushing for each of the bearings 40 permits the necessary swinging movementl of the crank arm 35 about the torsion rod 31 as an axis and at the same time avoids the necessity for lubrication and the liability for squeaks. At the same time this sleeve 44 permits the necessary twisting movement of the torsion rod 31, this torsion rod twisting to a progressively greater degree as it approaches its live end 46. The opposite or dead end 41 is restrained against rotation and for this purpose it is shown as deformed so as to be out of round and fitted in a correspondingly shaped socket of a socket member 49 which can be secured to the vehicle frame in any suitable manner. Thus, the angular movement of the torsion rod 31 in providing the necessary spring resistance for the suspension is much greater at the right hand bearing 40, as viewed in Fig. 4. than at the left hand bearing 40, as viewed in this same figure, this progressive increasing twisting of the torsion rod 31 as it approaches its anchored end 41 being permitted by the use of the rubber sleeve 44 as the bushings for the various bearings 40.

Between the front pair of bearings 40 of the crank arm 35 and between its rear pair of bearings 40, the torsion rod 31 is secured to the frame I0 of thevehicle by a bearing indicated generally at 50. As best shown in Fig. 5, each of these bearings comprises a bracket 5I which is secured to the corresponding longitudinal side bar Il of the frame I0 and formed on its underside to provide a half bearing socket` To the underside of each bracket 5I, by meansof screws 52 or in any other suitable manner, is secured a half bearing cap 53 which compresses a rubber bushing 54 into firm engagement with the corresponding part of the rubber sleeve 44 which forms the bushings for the bearings 49, the bushings 44 and 54 being thereby pressed into firm engagement with the corresponding part of the torsion rod 31, the torsion rod being thereby permitted to oscillate in the bearings 50. The use of the two rubber bushings 44 Aand k54 in the main supporting bearings 50 also permits the progressive twisting of the torsion rod 31 to provide the spring resistance for the spring suspension, the necessarily greater degree of twisting movement in the right hand main bearing 50, as viewed in Fig. 4, as compared with the left hand bearing 50 in this figure, being permitted by the use of rubber bushings in these bearings. The rear extremity of the torsion rod 31 is positively connected to the rear extremity of the crank arm 35 so that the oscillating movement of the crank arm 35 is transmitted directly to the rear or live end of the torsion rod 31. For this purpose the rear or live end 46 of the torsion rod 31 is preferably ovalled in the manner set forth in my Patent No. 2,213,004 granted August 21, i940,l for a Torsion rod mounting. This ovalled rear end of the torsion rod is fitted in a correspondingly shaped bore 58 provided in a socket member 59, the rear end of this bore being preferably closed by a removable cap 60. As best shown in Figs. 4 and '1, the socket member 59 is provided with a laterally l'extendingA arm 5| which is fitted against the flat end face 62 at the rear of the crank arm 35. 'A radially extending key 63 is preferably inserted in keyways provided in these parts and the arm 6I of each socket 59 is secured to the end of the crank arm 35 by a plurality ofl screws 54 or in any other suitable manner. It will therefore be seen that each socket member 59 is fast to the rear end of the corresponding crank arm 35 and that therefore the oscillation of the crank armi35 through its bearing 40 effects a corresponding twisting of the live end 46 of its torsion rod, this twisting movement of its torsion/ rod beingpermitted by the bearings 50.

The opposite or dead end v41 as fitted into a correspondingly. ovalled'bore of the socket member 49, this socket member being` shown as suitably secured to the corresponding sidebar II of theframe I0.

In the operation of the' suspensiomj*the'.'ufJey ward movement of one end of the' axle ,I3

through its shackles and 26` swings the outer of .the trsin rod 431 is also preferably ovalled in the mannerryset forthjin my Patent No. 2,213,004 andis shown.-

end of its crank arm upwardly, this c rank'arm rotating about its bearings which pivotally support the crank arrn on'its torsion vrod 31, this -torsion rod being in turn supported adjacent the bearings 40 by its bearings 50 which are lsecured to the main frame I 0 of the vehicle.'4 Thesebearings`40 and are bushed by the common rubber sleeve'44 which is distorted to permit the necessaryA movement of the crank arm 35,v andthe bearings supportingthe torsion rod 31 are additionally bushed with short rubber bushings 54,"th'ese Yadditional rubber bushings 54 being provided to accommodate the increased force imposed upon the bearings 50 as comparedwith the bearings 40. While a small twisting force is directly appliedto the torsion rod 31 through' the rubber bushed bearings 40, the `principal connection between each crank arm 35 and the. torsion rod 31 is through the socketmember 59 secured to one end of the crank arm 35 and whichhas an ovalled socket 58 receiving the ovalled 4"live end 46 of the torsion rod 31. Through the'socket member 59 it will be seen that the upward movement of the axle I3 jwill, twist the'torsion rod 31. 'This ltorque o f'the torsion rod 31 is transmitted to the dead"I end 41 of the torsion rod which is shown as anchored in the socket member 4G secured to the frame III of the vehicle. It will therefore be'seen that the torsion rods providel the necessary resil forming the vsubject of ience in the suspension this invention.

'It will be noted that the shackles 25 and `2li are inclined upwardly and inwardlyirom the crank arm pivot pins I1 to the axle pivot pins 30.

This upward and inward inclined arrangement of' the shackles tends to causeeach axle to centralize itself in a direction transverse of the frame and enables the action of gravity to geometrically and resiliently resist any such movementof the axleaway from its central position.' This permits the vehicle frame I0 to move substantially straight ahead despite a certain amount of.'

This arrangement lateral movement of the axle. of the shackles further provides high and wide pivot'positions whichl provides increased stability in that it provides eiective spring centers which can be as wide or wider than the track `of the vehicle. Further, this arrangement Aof "thev shackles reduces sidesway, the high and wide nivu 141` and the saine reference numerals have theree fore been' i?Dplied..` f .Inste larly', instead of the continuous l sleeve 1 7 an individual rubber? bushing isprcnde; for each 4of these bearings. The"ri/ibberbush@- ings 54a, f or thebe'arings. are. thicker ,thanfthe rubber bushing'sfua. 'for the bearings 40 because. of the heavier lo bearings 5i);V

.From the foregoing;

present invention' ,'provides'ja 1 su'spe'nsioriV f attaining the yobjects and havingthelv many oper.

ating and` structural vantages' set ior thfand at thesametimepro 'de` a suspension in which' a. separatefjournal "pin 'f orfthe crank'- arns'fis ,eliminated, the live endv of the torsion"`xfod` itself b 'eing`u 'sed` in substitution vfor suchfa' journal pin V and the ,necessary bearings for such noyelfstructure' being bushed with rubber` orother- Spit,

resilient plastic materiflso asjtofavoid'the neces-,L sity 'forflubrication nl 'rii-tl`ie` likelihnod of any'.`

noise developing,` the 'rubberfbushngs at the same time :permitting the'L freerelativeA 'm'ov 1 the different 'partsof he torsion ri'idLQv r 1. A" vehicle 'spring susp'ension; "comprising, frame, anaxlefhavin'g' a wheel joirrnfle"d thereon; a bearingmountedp onfsjaidjrame adjacent said axle with its'axis exter1ling' generallyatright. angles to vsaid axle, ja jtorslionrbdh'avingone en'd directly vjournal'ed'in s d"bear in'g`.me ans mounted'on saidvframeadJ e ltoand rstrf'i'in-v ing the"rotat ion of the bp'p s itu ndfofsa'aidtojr!4 sion rod, aV crank armha, iffof bearings directlyjournaledon said torsion'rod oxijoppo-y site sides of said rst bearing, means operative]yf connecting said crank arm to sa'idonefe'nd of said torsion rod, and eans pifvot'ally connected'tq said crank arm'andt'o saidaxle.

` 2. A `vehicleispring suspension, 1comprising"a frame, an axle having a'wheel viournaled thereon, a bearing mounted onsaid 'frame adjacent said` axle'with itsfaxis extending generally at'right' angles to said axle, ators'ion rod having one end"v directly journaled ,in said 'be'aring, means mounted on said frame' adjacent'to and restrain-rv ing therotation of the opposite end of saidftorsioni rod, va crank, arm having a pair'of bearingsy directly' journaledY on said torsion rod on oppo.

site sides'of a vertical plane extending'throug'h the axis o f said axle, means operatively con? necting said crank arm to said one end :of said. torsion rod,l andv4 said cran' k'a rm andfto' said axle.

3. A vehicle spring suspension, comprising a V frame, lan axle' havingza wheel" journaled there-` on, apairoi coaxial bearings mounted on said'.

frame adjacent saidaxle in spaced relation to. A

eachother `With the axis of said bearings'l ex'.

tending generally at right angles to said axle, 'a

torsion rod having one end directly journaled in said pair of bearings, means mounted on said frame adjacent to and restraining the rotation of thefopposite end of said torsion rod, a crank arm having a pair of spaced bearings each joumaled on said. torsion rod adjacent one of said rst ad, however,`, ,or the continuous sleeve l44` forming the rubber bushing "for each oithev arm bearings `4l), as in the forni fthelirivehtipn'" shown? iny Figs. 1-7,' thes`e rubber bushing"s,4 4a are shown as f,individu'allyy provided in Teach' of the bearings 40 around the torsion rod 31;., "Simi-Q ad which isfimposed'pp'on these'.v

means 'pivotally y connected to said ,crank` arm. to said. one end ot. said torsion4 rodi andmeans- .pivotally connected. to said crank saidaxle.. 4e Av vehicle. spring suspension, comprising a frame, anzaxle having a wheel .iournaledithereon, a pair of coaxial bearings` mounted on saidv frame. adiacent said. axle inspaced relatlonto eachother withV theA axisy oi'saidalbeangs ex' tending generally at right angles to said.; axle, a

torsi'cimrodl having one end directly iournaled; in a. said. pair' of bearings; means-mountedxon,

one end of said torsion rod, andlmeanspivotally' connected to said crank arm and 'to-said axle.

5. f A;` vehicle spring suspension, ,comprising a y frame,y an axle having. a wheel journaled'ithereon; a bearingv block mountedv on Asaid frameadjacent to said axle and'forrned to provide a cylindrical bore with: its axis extend-ingr generally V atv right.`

anglesv to said axle, a torsionrod: having one end arranged in said cylindrical bore,v means mountedl on. said' frame adjacent to and restraining the. rotation of the opposite end of said torsion rod,

a crank armfhavinga bearing socket 'surround---` ing said torsion rod adjacent said bearing block, a sleeve of a soft, resilient plastic material surrounding said torsion rod andhavingonepart arranged' in said cylindrical bore. and another part arranged in said socket, mean operatively'` connecting said crank arm to said one end of said torsion rod, and means pivotally connected to said crank arm andv to said axle.

6. A vehicle spring suspension',v comprising` a frame. an axle havinga wheel journaled thereon, a bearing block mounted on said frameadjacent to said axle andformed to provide a. cylindrical bore with its axis extending generally at right angles to said axle, e, torsion rod. having one end arranged in said cylindrical bore,. means mounted on said frame adjacent'to andrestraining the rotation of the opposite end of said 'torsion rod, a crank arm having a bearing socket surrounding said torsion rod adjacent; saldi bearing block, a sleeve of a soft, resilient plastic material surrounding said torsion rod and having one part arranged lin saidA cylindrical bore-and another part arranged in said socket and another part extendingalong said torsion rod, means for clamping said last extendingpart oi'v said sleeve to said torsion rod, means operatively connecting said crank arm to said one end of' said4 torsion rod, and meansrpivotally'connectedtozsaid crank arm andto said axle.` K

7. Ay vehicle spring suspension, Vcomprising a' frame, an axle having a wheel journaled thereon,

a pair of bearing blocks. mounted on said frame each formed to provide a cylindrical bore ar-lranged coaxially with the axis. arranged,gener-l ally at right'angles to said axle, a torsion rodv having one end arranged in said bores, means mounted on said frame adjacent to and restraining the rotation oi' the opposite endl of said. toroneoi said bearing blocks, a continuous. sleeve pair. ofi bearings, meansk operatively connectingY sionV rod, a crank arm formed ,to provide .two pairs of bearing sockets surrounding said torsion rod, and each pair 'arranged on opposite sides of of a soft., resilient plastic material having parts compressed in each of said cylindrical bores against saidtorsion rod and having other parts compressed in each of said sockets against said torsion rod,` means operatively connecting `said crankV arm to said one endof said torsionv rod',

and means rpivotally connected to said crank arm and to said axle.

8- A vehicle spring suspension, comprising a frame,l an axle having a wheel journaled there-1 on, abearing mounted on said frame adjacent .said axle with its axis extending generally at right'angles to said axle, a torsion rod having one'end. directly journaled in` said bearing and its extremity at said one end deformed into an out of 'round shape, means mounted. on said frameadjacent to and restraining the rotation of the opposite end of said torsion rod, a crank armY having a bearing directly journaled on` said' torsion rod adjacent said axle, a socket member secured to one axial extremity of said4 crank arm:

andhaving a socket fitting the deformed extremity of said torsion rod, and means pivotally connected to said crank arm and to said. axle.

9. A vehicle spring suspension, comprising a frame, an axle having a, wheel journaled thereon,

a pair of coaxial bearings mounted on said frame adjacent said axle in spaced relation tov each other with the axis of said bearings extending" generally at right angles to said axle, a torsion rod havingone end directly journaled in said bearings, means mounted on said frame and resaid crank arm to said one end of said torsion` rod, and means pivotally connected to said crank and to said axle.

10. A. vehicle spring suspension, comprising a' frame, an axle having a wheel journaled thereon, a pair of bearing members mounted on said frame adjacentv said axle in spaced relation to each other with the axis of said. bearings extending generally at right angles to said axle, a bushing of soft, resilient, plastic material in each of said bearing members, a torsion rod having one end directly journaled in said bushings, means mounted on said frame and restraining the rotation of the opposite end of said torsion rod, aiA

crank arm having a pair of spaced bearing sleeves jornaled on said torsion rod, a bushing of soft, resilient, plastic material in each of said bearing sleeves and compressed around said'. torsion rod, each of said last bushings being arranged inl Contact with a corresponding bushing of said first pair of bearing members, means operatively connecting said crank arm to said one end of said torsion rod, and means pivotally connected to said crank arm and to said axle.

ALBERT F. HICmMAN.4 

